Gypsum composites used in fire resistant building components

ABSTRACT

A composite product includes gypsum in an amount of 60 to 90% by weight, fibers in an amount of 1.5 to 26% by weight substantially homogeneously distributed through the composite, and a rheology-modifying agent in an amount of 0.5 to 6% by weight. The composite is caused or allowed to cure to form a cured composite. The cured composite is a fire resistant component used in a fire-rated door core, a fire-rated door or a fire-rated building panel. The fire resistant component may include a building panel, a door panel, a door core, a door rail, a door stile, a door lock block, a door border, or a door insert.

PRIORITY CLAIM AND CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a divisional application of U.S. patentapplication Ser. No. 13/610,542 filed on Sep. 11, 2012 and entitled“Gypsum Composites Used in Fire Resistant Building Components”, which isa continuation-in-part application of U.S. patent application Ser. No.13/603,405 filed on Sep. 4, 2012 and entitled “Gypsum Composites Used inFire Resistant Building Components”, which is a continuation-in-partapplication of: (1) U.S. patent application Ser. No. 13/538,788 filed onJun. 29, 2012 and entitled “Fire Rated Door Core”; and (2) U.S. patentapplication Ser. No. 13/538,828 filed on Jun. 29, 2012 and entitled“Fire Rated Door”. All these applications are hereby incorporated byreference in their entirety.

FIELD OF THE INVENTION

The present invention relates generally to the field of compositematerials and, more particularly, to gypsum composites used in fireresistant building materials.

BACKGROUND OF THE INVENTION

Many methods and techniques for manufacturing fire rated doors have beendeveloped over time. But most of these prior art designs do not lendthemselves well to fully automated manufacturing processes. Moreover,the prior art fire rated doors are expensive and require the internalmineral core. The internal core can be exposed in routed details and mayreduce the strength of the door as a result of the reduced thickness ofthe door panels. In addition, alignment of the panels during assemblycan be troublesome and require additional finishing to square the doorafter assembly.

Cement-based composites have been used in building materials for manyyears. For example, U.S. Pat. Nos. 5,549,859, 5,618,341, 5,631,097,5,641,584, 5,658,624, 5,702,787, 5,766,525, 5,798,151, 5,849,155 and6,379,446, and U.S. Published Patent Applications 2008/0099122,2010/0136269 and 2011/0120349 describe various compositions andprocesses for making extruded cement-based composite products, all ofwhich are hereby incorporated by reference in their entirety. Thesepatents and published patent applications, however, do not disclose fireresistant composite components having the necessary fire resistantcapabilities to produce doors, door cores and building panels that canreceive fire rated certifications.

SUMMARY OF THE INVENTION

The present invention provides fire resistant composite componentshaving the necessary fire resistant capabilities to produce doors, doorcores and building panels that can receive fire rated certifications. Inmost cases, the length and width of the fire rated door core will matchthe length and width specifications of the final door product. Thedimensions of the fire rated door core will typically be in widths ofthree feet and four feet and having a length ranging from seven feet toten feet. The thickness of the fire core can range from 1.50 inches to2.00 inches. In some cases, an exterior banding may be added to thesides and ends of the fire rated door core. In other cases, anintumescent banding may be added between the exterior banding and firerated door core.

More specifically, the present invention provides a composite productincluding gypsum in an amount of 60 to 90% by weight, fibers in anamount of 1.5 to 26% by weight substantially homogeneously distributedthrough the composite, and a rheology-modifying agent in an amount of0.5 to 6% by weight. The composite is caused or allowed to cure to forma cured composite. The cured composite is a fire resistant componentused in a fire-rated door core, a fire-rated door or a fire-ratedbuilding panel. The fire resistant component may include a buildingpanel, a door panel, a door core, a door rail, a door stile, a door lockblock, a door border, or a door insert.

In addition, the present invention provides a composite productincluding gypsum in an amount of 60 to 85% by weight, fibers in anamount of 1.5 to 5% by weight substantially homogeneously distributedthrough the composite, an aggregate in an amount of 10 to 25% by weightsubstantially homogeneously distributed through the composite, a starchin an amount of 2 to 7% by weight and a rheology-modifying agent in anamount of 0.5 to 4% by weight. The composite is caused or allowed tocure to form a cured composite. The fire resistant component may includea building panel, a door panel, a door core, a door rail, a door stile,a door lock block, a door border, or a door insert used in a fire-rateddoor core, a fire-rated door or a fire-rated building panel.

The present invention also provides a composite product including gypsumin an amount of 70 to 90% by weight, glass fibers in an amount of 2 to10% by weight substantially homogeneously distributed through thecomposite, cellulose fibers in an amount of 2 to 8% by weightsubstantially homogeneously distributed through the composite, polyvinylalcohol fibers in an amount of 1 to 4% by weight substantiallyhomogeneously distributed through the composite, polypropylene fibers inan amount of 0.3 to 4% by weight substantially homogeneously distributedthrough the composite, and a rheology-modifying agent in an amount of0.5 to 6% by weight. The composite is caused or allowed to cure to forma cured composite. The fire resistant component may include a buildingpanel, a door panel, a door core, a door rail, a door stile, a door lockblock, a door border, or a door insert used in a fire-rated door core, afire-rated door or a fire-rated building panel.

Moreover, the present invention provides a core for a fire rated doorthat includes a fire resistant center panel and an extruded fireresistant border. The fire resistant center panel has a bottom, a top, afirst side, a second side, a first end and a second end. The fireresistant center panel is made of a first fire resistant material thatincludes gypsum in an amount of 60 to 85% by weight, fibers in an amountof 1.5 to 5% by weight substantially homogeneously distributed throughthe composite, an aggregate in an amount of 10 to 25% by weightsubstantially homogeneously distributed through the composite, a starchin an amount of 2 to 7% by weight and a rheology-modifying agent in anamount of 0.5 to 4% by weight. The extruded fire resistant border isattached to the first side, the second side, the first end and thesecond end of the fire resistant center panel. The extruded fireresistant border is made of a second fire resistant material thatincludes gypsum in an amount of 70 to 90% by weight, glass fibers in anamount of 2 to 10% by weight substantially homogeneously distributedthrough the composite, cellulose fibers in an amount of 2 to 8% byweight substantially homogeneously distributed through the composite,polyvinyl alcohol fibers in an amount of 1 to 4% by weight substantiallyhomogeneously distributed through the composite, polypropylene fibers inan amount of 0.3 to 4% by weight substantially homogeneously distributedthrough the composite, and a rheology-modifying agent in an amount of0.5 to 6% by weight.

The present invention also provides a fire rated door that includes acore, a first decorative panel and a second decorative panel. The coreincludes: (a) a fire resistant center panel having a bottom, a top, afirst side, a second side, a first end and a second end, wherein thefire resistant center panel is made of a first fire resistant materialthat includes gypsum in an amount of 60 to 85% by weight, fibers in anamount of 1.5 to 5% by weight substantially homogeneously distributedthrough the composite, an aggregate in an amount of 10 to 25% by weightsubstantially homogeneously distributed through the composite, a starchin an amount of 2 to 7% by weight and a rheology-modifying agent in anamount of 0.5 to 4% by weight, and (b) an extruded fire resistant borderattached to the first side, the second side, the first end and thesecond end of the fire resistant center panel, wherein the extruded fireresistant border is made of a second fire resistant material thatincludes gypsum in an amount of 70 to 90% by weight, glass fibers in anamount of 2 to 10% by weight substantially homogeneously distributedthrough the composite, cellulose fibers in an amount of 2 to 8% byweight substantially homogeneously distributed through the composite,polyvinyl alcohol fibers in an amount of 1 to 4% by weight substantiallyhomogeneously distributed through the composite, polypropylene fibers inan amount of 0.3 to 4% by weight substantially homogeneously distributedthrough the composite, and a rheology-modifying agent in an amount of0.5 to 6% by weight. The first decorative panel is attached to the topof the fire resistant center panel and the extruded fire resistantborder. The second decorative panel is attached to the bottom of thefire resistant center panel and the extruded fire resistant border.

The present invention is described in detail below with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and further advantages of the invention may be betterunderstood by referring to the following description in conjunction withthe accompanying drawings, in which:

FIG. 1 is a perspective view of a door core for a fire rated door inaccordance with one embodiment of the present invention;

FIG. 2 is a perspective view of a door core for a fire rated door inaccordance with another embodiment of the present invention;

FIGS. 3A-3D are cross-sectional views of various interfaces of thecenter panel and the border of a door core in accordance with oneembodiment of the present invention;

FIG. 4 is a perspective view of a door core for a fire rated door inaccordance with another embodiment of the present invention;

FIG. 5 is a perspective view of a door core for a fire rated door inaccordance with another embodiment of the present invention;

FIG. 6 is a perspective view of a door core for a fire rated door inaccordance with another embodiment of the present invention;

FIG. 7 is a perspective view of a door core for a fire rated door inaccordance with another embodiment of the present invention;

FIG. 8 is a perspective view of a door core for a fire rated door inaccordance with another embodiment of the present invention;

FIG. 9 is a perspective view of a door core for a fire rated door inaccordance with another embodiment of the present invention;

FIG. 10A is an exploded perspective view of door core for a fire rateddoor in accordance with another embodiment of the present invention;

FIG. 10B is a cross-sectional view of the door core of FIG. 10A;

FIG. 11A is an exploded perspective view of a fire rated door inaccordance with one embodiment of the present invention;

FIG. 11B is a cross-sectional view of the fire rated door of FIG. 11A;

FIG. 11C is a cross-sectional view of an alternative version of the firerated door of FIG. 11A;

FIG. 12A is an exploded perspective view of a fire rated door inaccordance with another embodiment of the present invention;

FIG. 12B is a cross-sectional view of the fire rated door of FIG. 12A;

FIG. 13A is an exploded perspective view of a fire rated door inaccordance with another embodiment of the present invention;

FIG. 13B is a cross-sectional view of the fire rated door of FIG. 13A;

FIG. 13C is a cross-sectional view of an alternative version of the firerated door of FIG. 13A;

FIG. 14A is an exploded perspective view of a fire rated door inaccordance with another embodiment of the present invention;

FIG. 14B is a cross-sectional view of the fire rated door of FIG. 14A;

FIG. 14C is a cross-sectional view of an alternative version of the firerated door of FIG. 14A;

FIG. 15A is an exploded perspective view of a fire rated door inaccordance with another embodiment of the present invention;

FIG. 15B is a cross-sectional view of the fire rated door of FIG. 15A;

FIG. 16 is a flow chart of a method of manufacturing a door core for afire rated door in accordance with one embodiment of the presentinvention;

FIG. 17 is a flow chart of a method of manufacturing a door core for afire rated door in accordance with another embodiment of the presentinvention; and

FIG. 18 is a flow chart of a method of manufacturing a fire rated doorin accordance with one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

While the making and using of various embodiments of the presentinvention are discussed in detail below, it should be appreciated thatthe present invention provides many applicable inventive concepts thatcan be embodied in a wide variety of specific contexts. The specificembodiments discussed herein are merely illustrative of specific ways tomake and use the invention and do not delimit the scope of theinvention. The discussion herein relates primarily to fire rated doors,but it will be understood that the concepts of the present invention areapplicable to any type of door.

The composite product of the present invention provides fire resistantcomponents having the necessary fire resistant capabilities to producedoors, door cores and building panels that can receive fire ratedcertifications. The composite includes gypsum in an amount of 60 to 90%by weight, fibers in an amount of 1.5 to 26% by weight substantiallyhomogeneously distributed through the composite, and arheology-modifying agent in an amount of 0.5 to 6% by weight. The gypsumcan be 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%,73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%,87%, 88%, 89% or 90% by weight or other incremental percentage between.The fibers can be 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%,6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%,13%, 13.5%, 14%, 14.5%, 15%, 15.5%, 16%, 16.5%, 17%, 17.5%, 18%, 18.5%,19%, 19.5%, 20%, 20.5%, 21%, 21.5%, 22%, 22.5%, 23%, 23.5%, 24%, 24.5%,25%, 25.5% or 26% by weight or other incremental percentage between. Thefibers can be glass fibers, cellulose fibers polyvinyl alcohol fibers,polypropylene fibers, or a combination thereof. Other types of fiberscan be used. The rheology-modifying agent can be 0.5%, 0.6%, 0.7%, 0.8%,0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%,2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%,3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4%, 4.1%, 4.2%, 4.3%, 4.4%,4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, 5.6%,5.7%, 5.8%, 5.9% or 6% by weight or other incremental percentagebetween. The rheology-modifying agent can be hydroxypropoyl methylcelluose (HPMC), methyl hydroxyethyl cellulose (MHEC), hydroxyethylcellulose (HEC) or carboxymethyl cellulose (CMC). Other types ofrheology-modifying agent can be used.

The composite is caused or allowed to cure to form a cured composite.The actual component weights used will depend on the density desired forthe fire resistant component. The cured composite is a fire resistantcomponent used in a fire-rated door core, a fire-rated door or afire-rated building panel. The fire resistant component may include abuilding panel, a door panel, a door core, a door rail, a door stile, adoor lock block, a door border, or a door insert. The fire resistantcomponent typically has a cross-sectional thickness of 0.125 inches to 2inches, a width of 1 inch to 4 feet and a length of 3 to 10 feet.Moreover and unlike many prior art composite materials, the compositeproduct in accordance with the present invention does not include anycement or flyash.

The door core of the present invention provides the fire resistantcapabilities necessary to receive the necessary certification. Thelength and width of the fire core will match the length and widthspecifications of the final door product. The dimensions of the firecore will typically be in widths of three feet and four feet and havinga length ranging from seven feet to ten feet. The thickness of the doorcore will typically be between 0.125″ and 1.5″. A door manufacturer canuse any of the completed core designs described herein as the fireresistant core of the manufacturer's fire-rated door. The resulting firerated door can have fire ratings of 20-30, 45, 60, 90 or 120 minutesdepending on the configuration and materials used. The manufacturer willtypically finish the final door product by adding a final piece of woodor veneer to the door to provide the aesthetic appeal of the product.

Now referring to FIG. 1, a perspective view of a door core 100 for afire rated door in accordance with one embodiment of the presentinvention is shown. The core 100 includes a fire resistant center panel102 and an extruded fire resistant border 104. The fire resistant centerpanel 102 has a bottom (not shown), a top 106, a first side 108, asecond side 110, a first end 112 and a second end 114. The fireresistant center panel 102 is made of a first fire resistant materialthat is either pourable or extrudable. The first fire resistant materialcan be composed of gypsum, water, glass, a ceramic material, a celluloseor fiber material, and one or more binding agents. One example of such amaterial in accordance with the present invention is:

First Fire Resistant Material Component Range (% Wt.) Gypsum 60 to 85Glass Fiber 1.5 to 5   Lightweight Aggregate 10 to 25 Starch 2 to 7Rheology-Modifying Agent 0.5 to 4   Vermiculite or Clay  0 to 10The gypsum can be 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%,71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84% or85% by weight or other incremental percentage between. The glass fiberscan be 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5% or 5% by weight or otherincremental percentage between. The glass fibers can have a diameter of6 mm to 25 mm. The lightweight aggregate can be 10%, 11%, 12%, 13%, 14%,15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24% or 25% by weight orother incremental percentage between. The lightweight aggregate, such asPoraver® porous glass spheres, can have average particle diameters of 1to 2 mm or 2 to 4 mm. The starch can be 2%, 2.5%, 3%, 3.5%, 4%, 4.5%,5%, 5.5%, 6%, 6.5% or 7% by weight or other incremental percentagebetween. The starch is a pregelatinized or cook-up starch. Therheology-modifying agent can be cellulose ether, such as hydroxypropoylmethyl celluose (HPMC), methyl hydroxyethyl cellulose (MHEC),hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC) or similarmaterials. The rheology-modifying agent can be 0.5%, 0.6%, 0.7%, 0.8%,0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%,2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, 3.1%, 3.2%,3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9% or 4% by weight or otherincremental percentage between. A vermiculite or clay can also beincluded in the composition in 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or10% by weight or other incremental percentage between. Other materialscan be substituted as will be appreciated by those skilled in the art.

The extruded fire resistant border 104 is made of a second fireresistant material having a higher density than the first fire resistantmaterial so that second fire resistant material has holding capacity(e.g., fasteners will adhere to the second fire resistant material andremain fixed once installed) and can be shaped using an extrusionprocess. One example of such a material in accordance with the presentinvention is:

Second Fire Resistant Material Component Range (% Wt.) Gypsum 70 to 90Glass Fiber  2 to 10 Cellulose Fiber 2 to 8 Polyvinyl Alcohol (PVA)Fiber 1 to 4 Polypropylene (PP) Fiber 0.3 to 4   Rheology-ModifyingAgent 0.5 to 6  The gypsum can be 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%,81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89% or 90% by weight or otherincremental percentage between. The glass fibers can be 2%, 2.5%, 3%,3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5% or 10%by weight or other incremental percentage between. The glass fibers canhave a diameter of 6 mm to 25 mm. The cellulose fibers can be 2%, 2.5%,3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5% or 8% by weight orother incremental percentage between. The cellulose fibers can behardwood or softwood fiber. The polyvinyl alcohol (PVA) fibers can be1%, 1.5%, 2%, 2.5%, 3%, 3.5% or 4% by weight or other incrementalpercentage between. The PVA fibers can have a diameter of 6 mm to 10 mmwith a decitex of approximately 15. The polypropylene (PP) fibers can be0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%,1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%,2.9%, 3%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9% or 4% byweight or other incremental percentage between. The PP fibers can have adiameter of 6 mm to 25 mm. The rheology-modifying agent can be 0.5%,0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%,1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%,3%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4%, 4.1%,4.2%, 4.3%, 4.4%, 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5%, 5.1%, 5.2%, 5.3%,5.4%, 5.5%, 5.6%, 5.7%, 5.8%, 5.9% or 6% by weight or other incrementalpercentage between. The rheology-modifying agent can be a celluloseether, such as hydroxypropoyl methyl cellulose (HPMC), methylhydroxyethyl cellulose (MHEC), hydroxyethyl cellulose (HEC),carboxymethyl cellulose (CMC) or similar materials. Other materials canbe substituted as will be appreciated by those skilled in the art.

The extruded fire resistant border 104 can be made of a molded piece ofthe second fire resistant material (e.g., FIG. 1), or stiles and railsmade of the second fire resistant material that are glued or fastenedtogether (e.g., FIG. 4). The extruded fire resistant border 104 isattached to the first side 108, the second side 110, the first end 112and the second end 114 of the fire resistant center panel 102 usingglue, fasteners or a bonding process (e.g., pouring the first fireresistant material into a “mold” formed by the extruded fire resistantborder 104). Several examples of the interface between the extruded fireresistant border 104 and the fire resistant center panel 102 are shownin FIGS. 3A-3D.

The physical dimensions of the core 100 and other cores described belowin reference to FIGS. 2-10A and B, the fire resistant center panel 102and the extruded fire resistant border 104 will vary depending on thespecific application for which the door core is manufactured. Typicaldimensions may include, but are not limited to, 1.5″ to 2.0″ thicknessof the fire resistant panel 102 and the extruded fire resistant border104, a 7′ to 10′ overall length of the core 100, a 3′ to 4′ overallwidth of the core 100, a 1″ to 5″ width of the top and bottom portions(rails) of the extruded fire resistant border 104, and a 1″ to 5″ (e.g.,1.625″) width of the left and right portion (stiles) of the extrudedfire resistant border 104.

The core 100 and other cores described below in reference to FIGS. 2-10Aand B can be manufactured by assembling the fire resistant border 104,pouring the first fire resistant material in the area formed by the fireresistant border 104, and baking the core 100. Alternatively, the core100 can be manufactured by creating sheets of the first fire resistantmaterial and the second fire resistant material using an extrusionprocess, gang ripping the sheets of the second fire resistant materialto make the fire resistant border stiles and rails, finishing theextruded stiles and rails to profile or cut them to the desiredsmoothness, size and shape, and gluing or fastening the fire resistantborder stiles and rails to the fire resistant center panel 102.

Referring now to FIG. 2, a perspective view of a door core 200 for afire rated door in accordance with another embodiment of the presentinvention is shown. The core 200 includes a first fire resistant centerpanel 102 a, a second fire resistant center panel 102 b and an extrudedfire resistant border 104. The first fire resistant center panel 102 ahas a bottom (not shown), a top 106 a, a first side 108 a, a second side110 a, a first end 112 and a second end 202. The second fire resistantcenter panel 102 b has a bottom (not shown), a top 106 b, a first side108 b, a second side 110 b, a first end 204 and a second end 114. Thefirst fire resistant center panel 102 a and second fire resistant centerpanel 102 b are made of the first fire resistant material that is eitherpourable or extrudable. The extruded fire resistant border 104 is madeof the second fire resistant material having a higher density than thefirst fire resistant material so that second fire resistant material hasholding capacity (e.g., fasteners will adhere to the second fireresistant material and remain fixed once installed) and can be shapedusing an extrusion process. The extruded fire resistant border 104 alsoincludes a center rail 206 made of the second fire resistant material.The extruded fire resistant border 104 can be made of a molded piece ofthe second fire resistant material (e.g., FIG. 2), or stiles and railsmade of the second fire resistant material that are glued or fastenedtogether (e.g., FIG. 5). The extruded fire resistant border 104(including center rail 206) is attached to the first side 108 a, thesecond side 110 a, the first end 112 a and the second end 202 of thefire resistant center panel 102 a and the first side 108 b, the secondside 110 b, the first end 204 and the second end 114 of the second fireresistant center panel 102 b using glue, fasteners or a bonding process(e.g., pouring the first fire resistant material into a “mold” formed bythe extruded fire resistant border 104). Several examples of theinterface between the extruded fire resistant border 104 and the fireresistant center panels 102 a, 102 b are shown in FIGS. 3A-3D.

The physical dimensions of the core 200 and other cores described belowin reference to FIGS. 3-10A and B, the fire resistant center panels 102a, 102 b and the extruded fire resistant border 104 will vary dependingon the specific application for which the door core is manufactured.Typical dimensions may include, but are not limited to, 1.5″ thicknessof the fire resistant panels 102 a, 102 b and the extruded fireresistant border 104, a 7′ to 10′ overall length of the core 100, a 3′to 4′ overall width of the core 100, a 1″ to 5″ width of the top, bottomand center portions (rails) of the extruded fire resistant border 104,and a 1″ to 5″ (e.g., 1.625″) width of the left and right portion(stiles) of the extruded fire resistant border 104.

Now referring to FIGS. 3A-3D, cross-sectional views of variousinterfaces of the center panel 102 and the border 104 of a door core100, 200, 400, 500, 600, 700, 800 and 900 in accordance with oneembodiment of the present invention is shown. FIG. 3A shows a straightinterface wherein a glue is used to attach the extruded fire resistantborder 104 to the fire resistant center panel 102. Note that thestraight interface can be angled with respect to the top of the fireresistant center panel 102 instead of being substantially perpendicular.As shown in FIGS. 3B-3D, the extruded fire resistant border 104 can beattached to the fire resistant center panel 102 with a set ofmale-female connectors 300 formed in the extruded fire resistant border104 and the fire resistant center panel 102. The male-female connectorscan be triangular-shaped 300 a (FIG. 3B), curved-shaped 300 b (FIG. 3C)or 300 c (FIG. 3D), rectangular-shaped, angled, tongue-and-groove, or acombination thereof. A glue is typically used is used to attach theextruded fire resistant border 104 to the fire resistant center panel102, but fasteners or a bonding process can also be used.

Referring now to FIG. 4, a perspective view of a door core 400 for afire rated door in accordance with another embodiment of the presentinvention is shown. The core 400 includes a fire resistant center panel102 and an extruded fire resistant border 104. The fire resistant centerpanel 102 has a bottom (not shown), a top 106, a first side 108, asecond side 110, a first end 112 and a second end 114. The fireresistant center panel 102 is made of the first fire resistant materialthat is either pourable or extrudable. The extruded fire resistantborder 104 is made up of a first stile 402 (left), a second stile 404(right), a first rail 406 (top) and a second rail 408 (bottom). Thefirst stile 402 (left), second stile 404 (right), first rail 406 (top)and second rail 408 (bottom) are made of the second fire resistantmaterial having a higher density than the first fire resistant materialso that second fire resistant material has holding capacity (e.g.,fasteners will adhere to the second fire resistant material and remainfixed once installed) and can be shaped using an extrusion process. Thefirst stile 402 (left), second stile 404 (right), first rail 406 (top)and second rail 408 (bottom) are glued or fastened together and to thefire resistant center panel 102. The first stile 402 (left) is attachedto the first side 108 of the fire resistant center panel 102 using glue,fasteners or a bonding process. The second stile 404 (right) is attachedto the second side 110 of the fire resistant center panel 102 usingglue, fasteners or a bonding process. The first rail 406 (top) isattached to the first end 112 of the fire resistant center panel 102using glue, fasteners or a bonding process. The second rail 408 (top) isattached to the second end 114 of the fire resistant center panel 102using glue, fasteners or a bonding process. Several examples of theinterface between the stiles 402, 404, the rails 406, 408, and the fireresistant center panel 102 are shown in FIGS. 3A-3D.

Now referring to FIG. 5, a perspective view of a door core 500 for afire rated door in accordance with another embodiment of the presentinvention is shown. The core 500 includes a first fire resistant centerpanel 102 a, a second fire resistant panel 102 b and an extruded fireresistant border 104. The first fire resistant center panel 102 a has abottom (not shown), a top 106 a, a first side 108 a, a second side 110a, a first end 112 a and a second end 202. The second fire resistantcenter panel 102 b has a bottom (not shown), a top 106 b, a first side108 b, a second side 110 b, a first end 204 and a second end 114. Thefirst fire resistant center panel 102 a and second fire resistant centerpanel 102 b are made of the first fire resistant material that is eitherpourable or extrudable. The extruded fire resistant border 104 is madeup of a first stile 402 (left), a second stile 404 (right), a first rail406 (top), a second rail 408 (bottom) and a third rail or insert 502(center). The first stile 402 (left), second stile 404 (right), firstrail 406 (top), second rail 408 (bottom) and third rail or insert 502(center) are made of the second fire resistant material having a higherdensity than the first fire resistant material so that second fireresistant material has holding capacity (e.g., fasteners will adhere tothe second fire resistant material and remain fixed once installed) andcan be shaped using an extrusion process. The first stile 402 (left),second stile 404 (right), first rail 406 (top), second rail 408(bottom), third rail or insert 502 (center) are glued or fastenedtogether and to the fire resistant center panels 102 a and 102 b. Thefirst stile 402 (left) is attached to the first side 108 a, 108 b of thefire resistant center panels 102 a, 102 b using glue, fasteners or abonding process. The second stile 404 (right) is attached to the secondside 110 a, 110 b of the fire resistant center panels 102 a, 102 b usingglue, fasteners or a bonding process. The first rail 406 (top) isattached to the first end 112 of the first fire resistant center panel102 a using glue, fasteners or a bonding process. The second rail 408(bottom) is attached to the second end 114 of the second fire resistantcenter panel 102 b using glue, fasteners or a bonding process. The thirdrail or insert 502 (center) is attached to the second end 202 of thefirst fire resistant center panel 102 a and the first end 204 of thesecond fire resistant panel 102 b using glue, fasteners or a bondingprocess. Several examples of the interface between the stiles 402, 404,the rails 406, 408, and the fire resistant center panels 102 a, 102 bare shown in FIGS. 3A-3D. These interfaces can also be used between thefire resistant center panels 102 a, 102 b and the third rail or insert502 (center).

Referring now to FIG. 6, a perspective view of a door core 600 for afire rated door in accordance with another embodiment of the presentinvention is shown. The core 600 includes a fire resistant center panel102, an extruded fire resistant border 104 and a lock block 602. Thefire resistant center panel 102 has a bottom (not shown), a top 106, afirst side 108, a second side 110, a first end 112, a second end 114 anda cutout or notch 604 disposed in the first side 108. The fire resistantcenter panel 102 is made of the first fire resistant material that iseither pourable or extrudable. The lock block 602 is disposed within thecutout or notch 604 of the fire resistant center panel 102. The lockblock 602 is made of the second fire resistant material and is sized toaccommodate a door handle, lockset or other door hardware. The extrudedfire resistant border 104 is made up of a first stile 402 (left), asecond stile 404 (right), a first rail 406 (top) and a second rail 408(bottom). The first stile 402 (left), second stile 404 (right), firstrail 406 (top) and second rail 408 (bottom) are made of the second fireresistant material having a higher density than the first fire resistantmaterial so that second fire resistant material has holding capacity(e.g., fasteners will adhere to the second fire resistant material andremain fixed once installed) and can be shaped using an extrusionprocess. The first stile 402 (left), second stile 404 (right), firstrail 406 (top) and second rail 408 (bottom) are glued or fastenedtogether and to the fire resistant center panel 102 and lock block 602.The first stile 402 (left) is attached to the first side 108 of the fireresistant center panel 102 and the lock block 602 using glue, fastenersor a bonding process. The second stile 404 (right) is attached to thesecond side 110 of the fire resistant center panel 102 using glue,fasteners or a bonding process. The first rail 406 (top) is attached tothe first end 112 of the fire resistant center panel 102 using glue,fasteners or a bonding process. The second rail 408 (top) is attached tothe second end 114 of the fire resistant center panel 102 using glue,fasteners or a bonding process. Several examples of the interfacebetween the stiles 402, 404, the rails 406, 408, and the fire resistantcenter panel 102 are shown in FIGS. 3A-3D. These interfaces can also beused between the lock block 602, the fire resistant center panel 102 andthe first stile 402 (left).

Now referring to FIG. 7, a perspective view of a door core 700 for afire rated door in accordance with another embodiment of the presentinvention is shown. The core 700 includes a first fire resistant centerpanel 102 a, a second fire resistant panel 102 b and an extruded fireresistant border 104. The first fire resistant center panel 102 a has abottom (not shown), a top 106 a, a first side 108 a, a second side 110a, a first end 112 a and a second end 202. The second fire resistantcenter panel 102 b has a bottom (not shown), a top 106 b, a first side108 b, a second side 110 b, a first end 204 and a second end 114. Thefirst fire resistant center panel 102 a and second fire resistant centerpanel 102 b are made of the first fire resistant material that is eitherpourable or extrudable. The extruded fire resistant border 104 is madeup of a first stile 402 (left), a second stile 404 (right), a first rail406 (top), a second rail 408 (bottom) and a third rail or insert 702(middle). The first stile 402 (left), second stile 404 (right), firstrail 406 (top), second rail 408 (bottom) and third rail or insert 702(middle) are made of the second fire resistant material having a higherdensity than the first fire resistant material so that second fireresistant material has holding capacity (e.g., fasteners will adhere tothe second fire resistant material and remain fixed once installed) andcan be shaped using an extrusion process. The first stile 402 (left),second stile 404 (right), first rail 406 (top), second rail 408(bottom), third rail or insert 702 (middle) are glued or fastenedtogether and to the fire resistant center panels 102 a and 102 b. Thefirst stile 402 (left) is attached to the first side 108 a, 108 b of thefire resistant center panels 102 a, 102 b using glue, fasteners or abonding process. The second stile 404 (right) is attached to the secondside 110 a, 110 b of the fire resistant center panels 102 a, 102 b usingglue, fasteners or a bonding process. The first rail 406 (top) isattached to the first end 112 of the first fire resistant center panel102 a using glue, fasteners or a bonding process. The second rail 408(bottom) is attached to the second end 114 of the second fire resistantcenter panel 102 b using glue, fasteners or a bonding process. The thirdrail or insert 702 (middle) is attached to the second end 202 of thefirst fire resistant center panel 102 a and the first end 204 of thesecond fire resistant panel 102 b using glue, fasteners or a bondingprocess. The third rail or insert 702 (middle) is positioned and sized(e.g., 5″ to 10″ wide) to accept various attachments, such as a crashbar. Several examples of the interface between the stiles 402, 404, therails 406, 408, and the fire resistant center panels 102 a, 102 b areshown in FIGS. 3A-3D. These interfaces can also be used between the fireresistant center panels 102 a, 102 b and the third rail or insert 702(middle).

Referring now to FIG. 8, a perspective view of a door core 800 for afire rated door in accordance with another embodiment of the presentinvention is shown. The core 800 includes a first fire resistant centerpanel 102 a, a second fire resistant center panel 102 b, an extrudedfire resistant border 104 and a lock block 602. The first fire resistantcenter panel 102 a has a bottom (not shown), a top 106 a, a first side108 a, a second side 110 a, a first end 112 a, a second end 202 and acutout or notch 604 disposed in the first side 108 a. The second fireresistant center panel 102 b has a bottom (not shown), a top 106 b, afirst side 108 b, a second side 110 b, a first end 204 and a second end114. The first fire resistant center panel 102 a and second fireresistant center panel 102 b are made of the first fire resistantmaterial that is either pourable or extrudable. The lock block 602 isdisposed within the cutout or notch 604 of the first fire resistantcenter panel 102 a. The lock block 602 is made of the second fireresistant material and is sized to accommodate a door handle, lockset orother door hardware. The extruded fire resistant border 104 is made upof a first stile 402 (left), a second stile 404 (right), a first rail406 (top), a second rail 408 (bottom) and a third rail or insert 702(middle). The first stile 402 (left), second stile 404 (right), firstrail 406 (top), second rail 408 (bottom) and third rail or insert 702(middle) are made of the second fire resistant material having a higherdensity than the first fire resistant material so that second fireresistant material has holding capacity (e.g., fasteners will adhere tothe second fire resistant material and remain fixed once installed) andcan be shaped using an extrusion process. The first stile 402 (left),second stile 404 (right), first rail 406 (top), second rail 408(bottom), third rail or insert 702 (middle) are glued or fastenedtogether and to the fire resistant center panels 102 a, 102 b and lockblock 602. The first stile 402 (left) is attached to the first side 108a, 108 b of the fire resistant center panels 102 a, 102 b and the lockblock 602 using glue, fasteners or a bonding process. The second stile404 (right) is attached to the second side 110 a, 110 b of the fireresistant center panels 102 a, 102 b using glue, fasteners or a bondingprocess. The first rail 406 (top) is attached to the first end 112 ofthe first fire resistant center panel 102 a using glue, fasteners or abonding process. The second rail 408 (bottom) is attached to the secondend 114 of the second fire resistant center panel 102 b using glue,fasteners or a bonding process. The third rail or insert 702 (middle) isattached to the second end 202 of the first fire resistant center panel102 a, the first end 204 of the second fire resistant panel 102 b andthe lock block 602 using glue, fasteners or a bonding process. The thirdrail or insert 702 (middle) is positioned and sized (e.g., 5″ to 10″wide) to accept various attachments, such as a crash bar. Severalexamples of the interface between the stiles 402, 404, the rails 406,408, and the fire resistant center panels 102 a, 102 b are shown inFIGS. 3A-3D. These interfaces can also be used between the lock block602, the fire resistant center panel 102 a, the first stile 402 (left)and the third rail or insert 702 (middle).

Now referring to FIG. 9, a perspective view of a door core 900 for afire rated door in accordance with another embodiment of the presentinvention is shown. The core 900 includes a center panel 902 and anextruded fire resistant border 104. The center panel 902 has a bottom(not shown), a top 106, a first side 108, a second side 110, a first end112 and a second end 114. The center panel 902 is made of a corrugatedfiller (e.g., cardboard, etc.) having a plurality of voids (e.g.,honeycomb shaped, hexagon shaped, triangular shaped, etc.) and may befilled with an acoustical insulating material (e.g., fiberglass, foam,etc.). The extruded fire resistant border 104 is made up of a firststile 402 (left), a second stile 404 (right), a first rail 406 (top) anda second rail 408 (bottom). The first stile 402 (left), second stile 404(right), first rail 406 (top) and second rail 408 (bottom) are made ofthe second fire resistant material having a higher density than thefirst fire resistant material so that second fire resistant material hasholding capacity (e.g., fasteners will adhere to the second fireresistant material and remain fixed once installed) and can be shapedusing an extrusion process. The first stile 402 (left), second stile 404(right), first rail 406 (top) and second rail 408 (bottom) are glued orfastened together and to the center panel 902. The first stile 402(left) is attached to the first side 108 of the center panel 902 usingglue, fasteners or a bonding process. The second stile 404 (right) isattached to the second side 110 of the center panel 902 using glue,fasteners or a bonding process. The first rail 406 (top) is attached tothe first end 112 of the center panel 902 using glue, fasteners or abonding process. The second rail 408 (top) is attached to the second end114 of the center panel 902 using glue, fasteners or a bonding process.Several examples of the interface between the stiles 402, 404, the rails406, 408, and the fire resistant center panel 902 are shown in FIGS.3A-3D. Note that the center panel 902 is not suitable for forming a fireresistant door alone. Fire resistant materials or panels must beinstalled on the top 106 and bottom (not shown) of the center panel 902in order to make a fire resistant door. For example, the center panel902 can be used in the doors 1100 (FIG. 11A), 1200 (FIG. 12A) and 1300(FIG. 13A) if panels 1102, 1102 and 1302, respectively, are made of afire resistant material (e.g., the second fire resistant material,etc.).

Referring now to FIG. 10A, an exploded perspective view of door core1000 for a fire rated door in accordance with another embodiment of thepresent invention is shown. The core 1000 includes a fire resistantcenter panel 102 or 1002 disposed between a top insulating panel 902 aand a bottom insulating panel 902 b, and an extruded fire resistantborder 104 around the three panels 902 a, 102 (or 1002) and 902 b. Thefire resistant center panel 102 is made of the first fire resistantmaterial that is either pourable or extrudable. The fire resistantcenter panel 1002 is made of the second fire resistant material that iseither pourable or extrudable. The top insulating panel 902 a and bottominsulating panel 902 b are made of a corrugated filler (e.g., cardboard,etc.) having a plurality of voids (e.g., honeycomb shaped, hexagonshaped, triangular shaped, etc.) and may be filled with an acousticalinsulating material (e.g., fiberglass, foam, etc.). The three panels 902a, 102 (or 1002) and 902 b are typically glued together. The fireresistant center panel 102 or 1002 has a bottom (not shown), a top 106,a first side 108, a second side 110, a first end 112 and a second end114. The extruded fire resistant border 104 is made up of a first stile402 (left), a second stile 404 (right), a first rail 406 (top) and asecond rail 408 (bottom). The first stile 402 (left), second stile 404(right), first rail 406 (top) and second rail 408 (bottom) are made ofthe second fire resistant material having a higher density than thefirst fire resistant material so that second fire resistant material hasholding capacity (e.g., fasteners will adhere to the second fireresistant material and remain fixed once installed) and can be shapedusing an extrusion process. The first stile 402 (left), second stile 404(right), first rail 406 (top) and second rail 408 (bottom) are glued orfastened together and to the three panels 902 a, 102 (or 1002) and 902b. The first stile 402 (left) is attached to the first side 108 of thethree panels 902 a, 102 (or 1002) and 902 b using glue, fasteners or abonding process. The second stile 404 (right) is attached to the secondside 110 of the three panels 902 a, 102 (or 1002) and 902 b using glue,fasteners or a bonding process. The first rail 406 (top) is attached tothe first end 112 of the three panels 902 a, 102 (or 1002) and 902 busing glue, fasteners or a bonding process. The second rail 408 (top) isattached to the second end 114 of the three panels 902 a, 102 (or 1002)and 902 b using glue, fasteners or a bonding process. Several examplesof the interface between the stiles 402, 404, the rails 406, 408, andthe fire resistant center panel 102 are shown in FIGS. 3A-3D. FIG. 10Bis a cross-sectional view of the door core of FIG. 10A.

Note that the cores shown in FIGS. 1-10A and B, and described above mayalso include a top panel attached to the top of the core 100, 200, 300,400, 500, 600, 700, 800, 900 or 1000, or a bottom panel attached to thebottom of the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000,or both the top panel and the bottom panel attached to the core 100,200, 300, 400, 500, 600, 700, 800, 900 or 1000. Example of such aconfiguration is shown in FIGS. 13A and 14A. The top panel or the bottompanel can be a lignocellulosic substrate, a wood, a wood composite, amedium density fiberboard, a high density fiberboard, a particleboard, amasonite, a fiberglass, a metal, a plastic, a fire resistant panel, oneor more protective layers or a combination thereof. The one or moreprotective layers can be a fire resistant material, a blast resistantmaterial, a ballistic resistant material, a shielding material, achemical resistant material, a biohazard resistant material, a radiationresistant material, a dampening material, a grounding material,insulating material or a combination thereof. For example, the one ormore protective layers can be one or more gypsum boards, one or moremetallic sheets, one or more lead sheets, one or more Kevlar sheets, oneor more ceramic sheets, a layer of urethane foam, a layer of graphite, awire mesh or a combination thereof. Moreover, the core 100, 200, 300,400, 500, 600, 700, 800, 900 or 1000 and/or top or bottom panels can becoated with an intumescent or fire resistant material. Finally, notethat the rails shown in the figures can extend to the sides of the dooror core such that the stiles extend between the top and bottom rails.

Referring now to FIG. 11A, an exploded perspective view of a fire rateddoor 1100 in accordance with one embodiment of the present invention isshown. The fire rated door 1100 includes a core 100, 200, 300, 400, 500,600, 700, 800, 900 or 1000 (see FIGS. 1-10A and B and associateddescription for details), a first decorative panel 1102 and a seconddecorative panel 1104. The first and second decorative panel 1102 and1104 can be a lignocellulosic substrate, a wood, a wood composite, amedium density fiberboard, a high density fiberboard, a particleboard, amasonite, a fiberglass, a metal, a plastic, a fire resistant material ora combination thereof. The first decorative panel 1102 is attached tothe top of the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000using glue. The second decorative panel 1104 is attached to the bottomof the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000 usingglue. Note that the glue may have fire resistant properties or containan intumescent material. The first and second decorative panels 1102 and1104 have a slightly larger length and width to accommodate an exteriorbanding 1106 attached to each side and end of the core 100, 200, 300,400, 500, 600, 700, 800, 900 or 1000. The exterior banding 1106 can be afirst banding 1106 a, a second banding 1106 b, a third banding 1106 cand a fourth banding 1106 d. FIG. 11B shows a cross-sectional view ofthe fire rated door 1100. FIG. 11C shows a cross-sectional view of analternative version of the fire rated door 1100 in which an intumescentbanding material 1108 can also be disposed between the exterior banding1106 and the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000.

Now referring to FIG. 12A, an exploded perspective view of a fire rateddoor 1200 in accordance with another embodiment of the present inventionis shown. The fire rated door 1200 includes a core 100, 200, 300, 400,500, 600, 700, 800, 900 or 1000 (see FIGS. 1-10A and B and associateddescription for details), a first decorative panel 1102 and a seconddecorative panel 1104. The first and second decorative panel 1102 and1104 can be a lignocellulosic substrate, a wood, a wood composite, amedium density fiberboard, a high density fiberboard, a particleboard, amasonite, a fiberglass, a metal, a plastic, a fire resistant material ora combination thereof. Note that the first and second decorative panels1102 and 1104 may also have fire resistant properties. The firstdecorative panel 1102 is attached to the top of the core 100, 200, 300,400, 500, 600, 700, 800, 900 or 1000 using glue. The second decorativepanel 1104 is attached to the bottom of the core 100, 200, 300, 400,500, 600, 700, 800, 900 or 1000 using glue. Note that the glue may havefire resistant properties or contain an intumescent material. The firstand second decorative panels 1102 and 1104 have the same length andwidth as the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000.As a result, additional banding, rails and stiles are not needed. FIG.12B shows a cross-sectional view of the fire rated door 1200.

Referring now to FIG. 13A, an exploded perspective view of a fire rateddoor 1300 in accordance with another embodiment of the present inventionis shown. The fire rated door 1300 includes a core 100, 200, 300, 400,500, 600, 700, 800, 900 or 1000 (see FIGS. 1-10A and B and associateddescription for details), a first protective panel or layer 1302 (alsoreferred to as a top panel), a first decorative panel 1102, a secondprotective panel or layer 1304 (also referred to as a bottom panel) anda second decorative panel 1104. The first protective panel or layer 1302and the second protective panel or layer 1304 can be a fire resistantmaterial, a blast resistant material, a ballistic resistant material, ashielding material, a chemical resistant material, a biohazard resistantmaterial, a radiation resistant material, a dampening material, agrounding material, insulating material or a combination thereof. Forexample, the first protective panel or layer 1302 and the secondprotective panel or layer 1304 can be one or more gypsum boards, one ormore metallic sheets, one or more lead sheets, one or more Kevlarsheets, one or more ceramic sheets, a layer of urethane foam, a layer ofgraphite, a wire mesh or a combination thereof. A 120 minute fire rateddoor can be obtained by using a dense fire resistant material, such assecond fire resistant material, as the first and second protectivepanels or layers 1302 and 1304. The first and second decorative panel1102 and 1104 can be a lignocellulosic substrate, a wood, a woodcomposite, a medium density fiberboard, a high density fiberboard, aparticleboard, a masonite, a fiberglass, a metal, a plastic, a fireresistant material or a combination thereof. The first decorative panel1102 is attached to the top of the first protective panel or layer 1302using glue. The first protective panel or layer 1302 is attached to thetop of the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000using glue. The second decorative panel 1104 is attached to the bottomof the second protective panel or layer 1304 using glue. The secondprotective panel or layer 1304 is attached to the bottom of the core100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000 using glue. Notethat the glue may have fire resistant properties or contain anintumescent material. The first and second decorative panels 1102, 1104and first and second protective panels or layers 1302, 1304 have thesame length and width as the core 100, 200, 300, 400, 500, 600, 700,800, 900 or 1000. As a result, additional banding, rails and stiles arenot needed. FIG. 13B shows a cross-sectional view of the fire rated door1300. FIG. 13C shows a cross-sectional view of an alternative version ofthe fire rated door 1300 in which the first and second decorative panels1102 and 1104 have a slightly larger length and width to accommodate anexterior banding 1106 attached to each side and end of the core 100,200, 300, 400, 500, 600, 700, 800, 900 or 1000. As shown in FIG. 11A,the exterior banding 1106 can be a first banding 1106 a, a secondbanding 1106 b, a third banding 1106 c and a fourth banding 1106 d. Inaddition, an alternative version of the fire rated door 1300 can befabricated in which an intumescent banding material 1108 is disposedbetween the exterior banding 1106 and the core 100, 200, 300, 400, 500,600, 700, 800, 900 or 1000 (see FIG. 11C).

Now referring to FIG. 14A, an exploded perspective view of a fire rateddoor 1400 in accordance with another embodiment of the present inventionis shown. The fire rated door 1400 includes a core 100, 200, 300, 400,500, 600, 700, 800, 900 or 1000 (see FIGS. 1-10A and B and associateddescription for details), a first insulating panel or layer 1402, afirst decorative panel 1102, a second insulating panel or layer 1404 anda second decorative panel 1104. The first insulating panel or layer 1402and the second protective panel or layer 1404 is made of a corrugatedfiller (e.g., cardboard, etc.) having a plurality of voids (e.g.,honeycomb shaped, hexagon shaped, triangular shaped, etc.) filled withan insulating and/or fire resistant material (e.g., fiberglass, foam,etc.). The first and second decorative panel 1102 and 1104 can be alignocellulosic substrate, a wood, a wood composite, a medium densityfiberboard, a high density fiberboard, a particleboard, a masonite, afiberglass, a metal, a plastic, a fire resistant material or acombination thereof. The first decorative panel 1102 is attached to thetop of the first insulating panel or layer 1402 using glue. The firstinsulating panel or layer 1402 is attached to the top of the core 100,200, 300, 400, 500, 600, 700, 800, 900 or 1000 using glue. The seconddecorative panel 1104 is attached to the bottom of the second insulatingpanel or layer 1404 using glue. The second insulating panel or layer1404 is attached to the bottom of the core 100, 200, 300, 400, 500, 600,700, 800, 900 or 1000 using glue. Note that the glue may have fireresistant properties or contain an intumescent material. The first andsecond decorative panels 1102, 1104 and first and second insulatingpanels or layers 1402, 1404 have the same length and width as the core100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000. As a result,additional banding, rails and stiles are not needed. FIG. 14B shows across-sectional view of the fire rated door 1400. FIG. 14C shows across-sectional view of an alternative version of the fire rated door1400 in which the first and second decorative panels 1102 and 1104 havea slightly larger length and width to accommodate an exterior banding1106 attached to each side and end of the core 100, 200, 300, 400, 500,600, 700, 800, 900 or 1000. As shown in FIG. 11A, the exterior banding1106 can be a first banding 1106 a, a second banding 1106 b, a thirdbanding 1106 c and a fourth banding 1106 d. In addition, an alternativeversion of the fire rated door 1400 can be fabricated in which anintumescent banding material 1108 is disposed between the exteriorbanding 1106 and the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or1000 (see FIG. 11C).

Referring now to FIG. 15A, an exploded perspective view of a fire rateddoor 1500 in accordance with another embodiment of the present inventionis shown. The fire rated door 1500 includes a core 100, 200, 300, 400,500, 600, 700, 800, 900 or 1000 (see FIGS. 1-10 and associateddescription for details), a first decorative panel 1102, a seconddecorative panel 1104 and four rails 1502. Alternatively, the core 100,200, 300, 400, 500, 600, 700, 800, 900 or 1000 can be a single sheet offire resistant material, including, but not limited to the first fireresistant material. The back side of first and second decorative panel1102 and 1104 include a notch or cutout 1504 along the left and rightsides that is sized to fit each rail 1502. Each rail 1502 is made of thesecond fire resistant material or other suitable material. In oneexample, the rails have a height of 11/16″ and width of 1″. The firstand second decorative panel 1102 and 1104 can be a lignocellulosicsubstrate, a wood, a wood composite, a medium density fiberboard, a highdensity fiberboard, a particleboard, a masonite, a fiberglass, a metal,a plastic, a fire resistant material or a combination thereof. Note thatthe first and second decorative panels 1102 and 1104 may also have fireresistant properties. The first decorative panel 1102 is attached to thetop of the core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000 orsingle sheet of fire resistant material using glue. The seconddecorative panel 1104 is attached to the bottom of the core 100, 200,300, 400, 500, 600, 700, 800, 900 or 1000 or single sheet of fireresistant material using glue. Note that the glue may have fireresistant properties or contain an intumescent material. The first andsecond decorative panels 1102 and 1104 have the same length and width asthe core 100, 200, 300, 400, 500, 600, 700, 800, 900 or 1000 or singlesheet of fire resistant material. As a result, additional banding, railsand stiles are not needed. FIG. 15B shows a cross-sectional view of thefire rated door 1400.

Now referring to FIG. 16, a flow chart of a method 1600 of manufacturinga door core for a fire rated door in accordance with one embodiment ofthe present invention is shown. A fire resistant center panel having abottom, a top, a first side, a second side, a first end and a second endis provided in block 1602, wherein the fire resistant center panel ismade of a first fire resistant material. A first stile of an extrudedfire resistant border is attached to the first side of the fireresistant center panel in block 1604, wherein the extruded fireresistant border is made of a second fire resistant material having ahigher density than the first fire resistant material. A second stile ofthe extruded fire resistant border is attached to the second side of thefire resistant center panel in block 1606. A first rail of the extrudedfire resistant border is attached to the first end of the fire resistantcenter panel and the first stile and the second stile of the extrudedfire resistant border in block 1608. A second rail of the extruded fireresistant border is attached to the second end of the fire resistantcenter panel and the first stile and the second stile of the extrudedfire resistant border in block 1610. An optional step may includeforming a fire rated door by attaching a first decorative and a seconddecorative panel to the top and bottom, respectively, of the fireresistant center panel, the first stile, the second stile, the firstrail and the second rail of the extruded border in block 1612.Additional elements can be added as described in reference to FIGS.11-15A and B. Another optional step may include coating the fireresistant center panel and the extruded fire resistant border with anintumescent or fire resistant material. Note that the method 1600 can beperformed as part of a continuous manufacturing process.

In one embodiment, a notch is formed in the first side of the fireresistant center panel, a fire resistant lock block is inserted withinthe notch and the fire resistant lock block is attached to the fireresistant center panel and the extruded fire resistant border, whereinthe fire resistant lock block is made of the second fire resistantmaterial. In another embodiment, the fire resistant center panelincludes: (a) a first fire resistant center panel disposed between thefirst side and the second side proximate to the first end, wherein thefirst fire resistant center panel is made of the first fire resistantmaterial; (b) a second fire resistant center panel disposed between thefirst side and the second side proximate to the second end, wherein thesecond fire resistant center panel is made of the first fire resistantmaterial; and (c) a fire resistant insert disposed between and attachedto the first fire resistant center panel and the second fire resistantcenter panel, and extending between and attached to the extruded fireresistant border at the first side and the second side, wherein the fireresistant material is made of the second fire resistant material. In yetanother embodiment, a set of male-female connectors are formed in theextruded fire resistant border and the fire resistant center panel. Themale-female connectors can be triangular-shaped, curved-shaped,rectangular-shaped, angled, tongue-and-groove, or a combination thereof.

In another embodiment, the first fire resistant material is extruded ormolded to form the fire resistant center panel, and the second fireresistant material is extruded or molded to form the first stile, thesecond stile, the first rail and the second rail of the extruded fireresistant border. In yet another embodiment, the first fire resistantmaterial is extruded or molded to form the fire resistant center panel,and the second fire resistant material is extruded or molded to form asheet that is then gang ripped to form one or more of the first stile,the second stile, the first rail and the second rail of the extrudedfire resistant border. In either embodiment the panels, stiles and railsmay undergo one or more finishing steps (e.g., sanding, trimming,cutting, denibbing, etc.) so that the pieces have the proper smoothness,size and shape.

Furthermore, a top panel can be attached to the top of the fireresistant center panel and the extruded fire resistant border, or abottom panel can be attached to the bottom of the fire resistant centerpanel, or both the top panel and the bottom panel can be attached to thefire resistant center panel. The top panel or the bottom panel can be alignocellulosic substrate, a wood, a wood composite, a medium densityfiberboard, a high density fiberboard, a particleboard, a masonite, afiberglass, a metal, a plastic, one or more protective layers or acombination thereof. The one or more protective layers can be a fireresistant material, a blast resistant material, a ballistic resistantmaterial, a shielding material, a chemical resistant material, abiohazard resistant material, a radiation resistant material, adampening material, a grounding material, insulating material or acombination thereof. For example, the one or more protective layers canbe one or more gypsum boards, one or more metallic sheets, one or morelead sheets, one or more Kevlar sheets, one or more ceramic sheets, alayer of urethane foam, a layer of graphite, a wire mesh or acombination thereof.

Referring now to FIG. 17, a flow chart of a method 1700 of manufacturinga door core for a fire rated door in accordance with another embodimentof the present invention is shown. An extruded fire resistant border isprovided in block 1702. The extruded fire resistant border has a centralvoid and is manufactured by providing a first stile of the extruded fireresistant border, attaching a first rail of the extruded fire resistantborder to the first stile of the extruded fire resistant border,attaching a second rail of the extruded fire resistant border to thefirst stile and attaching a second stile of the extruded fire resistantborder to the first rail and the second rail of the extruded fireresistant border, wherein the extruded fire resistant border is made ofa second fire resistant material. The void within the extruded fireresistant border is filled with a first fire resistant material that hasa lower density than the second fire resistant material to form a fireresistant center panel in block 1704. The extruded fire resistant borderand first fire resistant material are baked or cured to set and fix thematerial in block 1706. Sanding or other finishing steps may beperformed thereafter. An optional step may include forming a fire rateddoor by attaching a first decorative and a second decorative panel tothe top and bottom, respectively, of the extruded fire resistant borderand fire resistant center panel in block 1708. Additional elements canbe added as described in reference to FIGS. 11-15. An optional step mayinclude coating the fire resistant center panel and the extruded fireresistant border with an intumescent or fire resistant material. Notethat the method 1700 can be performed as part of a continuousmanufacturing process.

In one embodiment, a notch is formed in the first side of the fireresistant center panel, a fire resistant lock block is inserted withinthe notch and the fire resistant lock block is attached to the fireresistant center panel and the extruded fire resistant border, whereinthe fire resistant lock block is made of the second fire resistantmaterial. In another embodiment, the fire resistant center panelincludes: (a) a first fire resistant center panel disposed between thefirst side and the second side proximate to the first end, wherein thefirst fire resistant center panel is made of the first fire resistantmaterial; (b) a second fire resistant center panel disposed between thefirst side and the second side proximate to the second end, wherein thesecond fire resistant center panel is made of the first fire resistantmaterial; and (c) a fire resistant insert disposed between and attachedto the first fire resistant center panel and the second fire resistantcenter panel, and extending between and attached to the extruded fireresistant border at the first side and the second side, wherein the fireresistant material is made of the second fire resistant material. In yetanother embodiment, a set of male-female connectors are formed in theextruded fire resistant border and the fire resistant center panel. Themale-female connectors can be triangular-shaped, curved-shaped,rectangular-shaped, angled, tongue-and-groove, or a combination thereof.

In another embodiment, the first fire resistant material is extruded ormolded to form the fire resistant center panel, and the second fireresistant material is extruded or molded to form the first stile, thesecond stile, the first rail and the second rail of the extruded fireresistant border. In yet another embodiment, the first fire resistantmaterial is extruded or molded to form the fire resistant center panel,and the second fire resistant material is extruded or molded to form asheet that is then gang ripped to form one or more of the first stile,the second stile, the first rail and the second rail of the extrudedfire resistant border.

Furthermore, a top panel can be attached to the top of the fireresistant center panel and the extruded fire resistant border, or abottom panel can be attached to the bottom of the fire resistant centerpanel, or both the top panel and the bottom panel can be attached to thefire resistant center panel. The top panel or the bottom panel can be alignocellulosic substrate, a wood, a wood composite, a medium densityfiberboard, a high density fiberboard, a particleboard, a masonite, afiberglass, a metal, a plastic, one or more protective layers or acombination thereof. The one or more protective layers can be a fireresistant material, a blast resistant material, a ballistic resistantmaterial, a shielding material, a chemical resistant material, abiohazard resistant material, a radiation resistant material, adampening material, a grounding material, insulating material or acombination thereof. For example, the one or more protective layers canbe one or more gypsum boards, one or more metallic sheets, one or morelead sheets, one or more Kevlar sheets, one or more ceramic sheets, alayer of urethane foam, a layer of graphite, a wire mesh or acombination thereof.

Now referring to FIG. 18, a flow chart of a method 1800 of manufacturinga fire rated door in accordance with one embodiment of the presentinvention is shown. A door core as shown in FIGS. 1-10 is provided inblock 1802. A first decorative panel is attached to a top of the doorcore in block 1804, and a second decorative panel is attached to abottom of the door core in block 1806. Additional elements can be addedas described in reference to FIGS. 11-14.

Although preferred embodiments of the present invention have beendescribed in detail, it will be understood by those skilled in the artthat various modifications can be made therein without departing fromthe spirit and scope of the invention as set forth in the appendedclaims.

What is claimed is:
 1. A fire resistant composite product comprising: acomposite comprising gypsum in an amount sufficient to provide fireresistance wherein the amount is 60 to 90% by weight, fibers in anamount of 1.5 to 26% by weight substantially homogeneously distributedthrough the composite, and a rheology-modifying agent in an amount of0.5 to 6% by weight; wherein the fibers comprise glass fibers, cellulosefibers, polyvinyl alcohol fibers and polypropylene fibers; wherein therheology-modifying agent comprises hydroxypropoyl methyl celluose(HPMC), methyl hydroxyethyl cellulose (MHEC), hydroxyethyl cellulose(HEC) or carboxymethyl cellulose (CMC); the composite is caused orallowed to cure to form a cured composite; and the cured composite is afire resistant component used in a fire-rated door core, a fire-rateddoor or a fire-rated building panel, wherein the fire resistantcomponent is selected from a building panel, a door panel, a door core,a door rail, a door stile, a door lock block, a door border, and a doorinsert.
 2. The fire resistant composite product as recited in claim 1,wherein the composite further comprises an aggregate in an amount of 10to 25% by weight substantially homogeneously distributed through thecomposite.
 3. The fire resistant composite product as recited in claim1, wherein the composite further comprises a starch in an amount of 2 to7% by weight.
 4. The fire resistant composite product as recited inclaim 1, wherein the composite further comprises a vermiculite or clayin an amount of 1 to 10% by weight substantially homogeneouslydistributed through the composite.
 5. The fire resistant compositeproduct as recited in claim 1, wherein the composite does not includeany cement or flyash.
 6. The fire resistant composite product as recitedin claim 1, wherein the glass fibers are in an amount of 1.5 to 5% byweight.
 7. The fire resistant composite product as recited in claim 1,wherein: the glass fibers are in an amount of 2 to 10% by weight; thecellulose fibers are in an amount of 2 to 8% by weight; the polyvinylalcohol fibers are in an amount of 1 to 4% by weight; and thepolypropylene fibers are in an amount of 0.3 to 4% by weight.
 8. A fireresistant composite product comprising: a composite consisting of gypsumin an amount sufficient to provide fire resistance wherein the amount is60 to 85% by weight, fibers in an amount of 1.5 to 5% by weightsubstantially homogeneously distributed through the composite, anaggregate in an amount of 10 to 25% by weight substantiallyhomogeneously distributed through the composite, a starch in an amountof 2 to 7% by weight and a rheology-modifying agent in an amount of 0.5to 4% by weight; the composite is caused or allowed to cure to form acured composite; and the cured composite is a fire resistant componentused in a fire-rated door core, a fire-rated door or a fire-ratedbuilding panel, wherein the fire resistant component is selected from abuilding panel, a door panel, a door core, a door rail, a door stile, adoor lock block, a door border, and a door insert.
 9. The fire resistantcomposite product as recited in claim 8, wherein the composite furthercomprises a vermiculite or clay in an amount of 1 to 10% by weightsubstantially homogeneously distributed through the composite.
 10. Thefire resistant composite product as recited in claim 8, wherein thefibers have a diameter of 6 mm to 25 mm.
 11. The fire resistantcomposite product as recited in claim 8, wherein the rheology-modifyingagent comprises hydroxypropoyl methyl celluose (HPMC), methylhydroxyethyl cellulose (MHEC), hydroxyethyl cellulose (HEC) orcarboxymethyl cellulose (CMC).
 12. The fire resistant composite productas recited in claim 8, wherein the aggregate have an average particlediameter of 1 to 4 mm.
 13. The fire resistant composite product asrecited in claim 8, wherein the fibers comprise glass fibers, cellulosefibers polyvinyl alcohol fibers, polypropylene fibers, or a combinationthereof.
 14. The fire resistant composite product as recited in claim 8,wherein the fire resistant component has a cross-sectional thickness of0.125 inches to 2 inches, a width of 1 inch to 4 feet and a length of 3to 10 feet.
 15. The fire resistant composite product as recited in claim8, wherein the composite does not include any cement or flyash.
 16. Afire resistant composite product comprising: a composite comprisinggypsum in an amount sufficient to provide fire resistance wherein theamount is 70 to 90% by weight, glass fibers in an amount of 2 to 10% byweight substantially homogeneously distributed through the composite,cellulose fibers in an amount of 2 to 8% by weight substantiallyhomogeneously distributed through the composite, polyvinyl alcoholfibers in an amount of 1 to 4% by weight substantially homogeneouslydistributed through the composite, polypropylene fibers in an amount of0.3 to 4% by weight substantially homogeneously distributed through thecomposite, and a rheology-modifying agent in an amount of 0.5 to 6% byweight; wherein the rheology-modifying agent comprises hydroxypropoylmethyl celluose (HPMC), methyl hydroxyethyl cellulose (MHEC),hydroxyethyl cellulose (HEC) or carboxymethyl cellulose (CMC); thecomposite is caused or allowed to cure to form a cured composite; andthe cured composite is a fire resistant component used in a fire-rateddoor core, a fire-rated door or a fire-rated building panel, wherein thefire resistant component is selected from a building panel, a doorpanel, a door core, a door rail, a door stile, a door lock block, a doorborder, and a door insert.
 17. The fire resistant composite product asrecited in claim 16, wherein the fibers have a diameter of 6 mm to 25mm.
 18. The fire resistant composite product as recited in claim 16,wherein the fire resistant component has a cross-sectional thickness of0.125 inches to 2 inches, a width of 1 inch to 4 feet and a length of 3to 10 feet.
 19. The fire resistant composite product as recited in claim16, wherein the composite does not include any cement or flyash.